Problem

Points

Score

1

10

 

2

15

 

3

15

 

4

10

 

5

15

 

6

20

 

7

15

 

Total

100

 

Physics 214 Spring 2001

Test 2, Mar 27

 

Name______________________

         

              

 

                        

                                                                                

           

Please show all work as this will be graded for partial credit. 

 

1.(10pts )  A baseball is struck by Sammy Sosa at 120.0 ft/s at 30 degrees above the horizontal

from a point 3 feet above home plate.  Will the ball clear the left field wall that is 10 feet high, and located 395 feet from home plate?

 

 

 

 

 

 

 

 

 

           

 2.) a)(7pts)Essay: What is the difference between mass and weight?

 

 

 

 

 

 

 

b)(8pts)  Essay: What is the difference between centripetal and centrifugal force?

 

 

 

 

 

 

 

3.) A 10 gram particle travels in a circular path of circumference 2 m, and makes 10 revolutions

per second. 

 

a)(5pts) On the diagram show the acceleration, position, and velocity vectors

 

 

 

 

 

 

 

 


b)(5pts) Find the centripetal acceleration.

 

 

 

 

 

c)(5pts) Find the centripetal force.

 

 

 

 

 

 

 

4.(10pts) A particle of mass 2 kg has an initial velocity of i – 2j m/s.  It is acted on by a force

.4i + j for 2 sec.  What is its final velocity?

 

 

 

 

 

 

 

 

 

5.(15pts )   A 15 kg picture is suspended with two wires, as shown.  If the wire used is rated at 100 N

should the picture be hung above a baby’s bed?

 

                            

                                                                       

 

 

                                                                                                                                                                                                                                                           

 

 

 

 

6.(20pts) A raft is floating west at 3 km/hour relative to land.  To a person on the raft, a water

skier appears to move away at 24 km/hour at 60 degrees S of W. 

 

a.(10pts) Draw a diagram showing the reference frames and vectors involved.

 

 

 

 

 

 

 

 

 

b.(10pts) What is the velocity of the water skier relative to the shore?

 

 

 

 

 

 

 

 

 

7.(15pts) Two blocks with masses m1 = .2 kg, and m2 = .5 kg are connected

by a massless rope, and slide on a frictionless surface as in the figure.  Find

the acceleration of the system and the tension in the rope.

 


                                  m1

                                                                        m2

 

 

 

 

 

 

 

 

Extra Credit (10pts): Do the same problem as 7, but include kinetic friction between the

large block and m1.  Find the coefficient of kinetic friction given the new acceleration = 5 m/s/s.